I asked:
> Is there any reason not to add an lutime() system call, analogously
> with chown and lchown?
There were no replies, so here's a patch for it (i386 only). I also
tried patching glibc and tar to make use of the new system call; see
http://rano.org/lutime/
A web search for lutime reveals that it is mentioned in passing in the
IEEE/POSIX standard and apparently some systems out there actually
have the function, but I don't know which.
Edmund
diff -ru linux-2.4.18/arch/i386/kernel/entry.S linux/arch/i386/kernel/entry.S
--- linux-2.4.18/arch/i386/kernel/entry.S Mon Feb 25 19:37:53 2002
+++ linux/arch/i386/kernel/entry.S Tue Jun 25 08:46:15 2002
@@ -634,6 +634,7 @@
.long SYMBOL_NAME(sys_ni_syscall) /* 235 reserved for removexattr */
.long SYMBOL_NAME(sys_ni_syscall) /* reserved for lremovexattr */
.long SYMBOL_NAME(sys_ni_syscall) /* reserved for fremovexattr */
+ .long SYMBOL_NAME(sys_lutime)
.rept NR_syscalls-(.-sys_call_table)/4
.long SYMBOL_NAME(sys_ni_syscall)
diff -ru linux-2.4.18/fs/open.c linux/fs/open.c
--- linux-2.4.18/fs/open.c Fri Oct 12 21:48:42 2001
+++ linux/fs/open.c Tue Jun 25 08:45:36 2002
@@ -229,21 +229,17 @@
* must be owner or have write permission.
* Else, update from *times, must be owner or super user.
*/
-asmlinkage long sys_utime(char * filename, struct utimbuf * times)
+static int utime_common(struct dentry * dentry, struct utimbuf * times)
{
int error;
- struct nameidata nd;
struct inode * inode;
struct iattr newattrs;
- error = user_path_walk(filename, &nd);
- if (error)
- goto out;
- inode = nd.dentry->d_inode;
+ inode = dentry->d_inode;
error = -EROFS;
if (IS_RDONLY(inode))
- goto dput_and_out;
+ goto out;
/* Don't worry, the checks are done in inode_change_ok() */
newattrs.ia_valid = ATTR_CTIME | ATTR_MTIME | ATTR_ATIME;
@@ -252,43 +248,62 @@
if (!error)
error = get_user(newattrs.ia_mtime, ×->modtime);
if (error)
- goto dput_and_out;
+ goto out;
newattrs.ia_valid |= ATTR_ATIME_SET | ATTR_MTIME_SET;
} else {
if (current->fsuid != inode->i_uid &&
(error = permission(inode,MAY_WRITE)) != 0)
- goto dput_and_out;
+ goto out;
}
- error = notify_change(nd.dentry, &newattrs);
-dput_and_out:
- path_release(&nd);
+ error = notify_change(dentry, &newattrs);
out:
return error;
}
+asmlinkage int sys_utime(char * filename, struct utimbuf * times)
+{
+ struct nameidata nd;
+ int error;
+
+ error = user_path_walk(filename, &nd);
+ if (!error) {
+ error = utime_common(nd.dentry, times);
+ path_release(&nd);
+ }
+ return error;
+}
+
+asmlinkage int sys_lutime(char * filename, struct utimbuf * times)
+{
+ struct nameidata nd;
+ int error;
+
+ error = user_path_walk_link(filename, &nd);
+ if (!error) {
+ error = utime_common(nd.dentry, times);
+ path_release(&nd);
+ }
+ return error;
+}
+
#endif
/* If times==NULL, set access and modification to current time,
* must be owner or have write permission.
* Else, update from *times, must be owner or super user.
*/
-asmlinkage long sys_utimes(char * filename, struct timeval * utimes)
+static int utimes_common(struct dentry * dentry, struct timeval * utimes)
{
int error;
- struct nameidata nd;
struct inode * inode;
struct iattr newattrs;
- error = user_path_walk(filename, &nd);
-
- if (error)
- goto out;
- inode = nd.dentry->d_inode;
+ inode = dentry->d_inode;
error = -EROFS;
if (IS_RDONLY(inode))
- goto dput_and_out;
+ goto out;
/* Don't worry, the checks are done in inode_change_ok() */
newattrs.ia_valid = ATTR_CTIME | ATTR_MTIME | ATTR_ATIME;
@@ -296,18 +311,44 @@
struct timeval times[2];
error = -EFAULT;
if (copy_from_user(×, utimes, sizeof(times)))
- goto dput_and_out;
+ goto out;
newattrs.ia_atime = times[0].tv_sec;
newattrs.ia_mtime = times[1].tv_sec;
newattrs.ia_valid |= ATTR_ATIME_SET | ATTR_MTIME_SET;
} else {
if ((error = permission(inode,MAY_WRITE)) != 0)
- goto dput_and_out;
+ goto out;
}
- error = notify_change(nd.dentry, &newattrs);
-dput_and_out:
- path_release(&nd);
+ error = notify_change(dentry, &newattrs);
out:
+ return error;
+}
+
+asmlinkage int sys_utimes(char * filename, struct timeval * utimes)
+{
+ struct nameidata nd;
+ int error;
+
+ error = user_path_walk(filename, &nd);
+
+ if (!error) {
+ error = utimes_common(nd.dentry, utimes);
+ path_release(&nd);
+ }
+ return error;
+}
+
+asmlinkage int sys_lutimes(char * filename, struct timeval * utimes)
+{
+ struct nameidata nd;
+ int error;
+
+ error = user_path_walk_link(filename, &nd);
+
+ if (!error) {
+ error = utimes_common(nd.dentry, utimes);
+ path_release(&nd);
+ }
return error;
}
diff -ru linux-2.4.18/include/asm-i386/unistd.h linux/include/asm-i386/unistd.h
--- linux-2.4.18/include/asm-i386/unistd.h Mon Feb 25 19:38:12 2002
+++ linux/include/asm-i386/unistd.h Tue Jun 25 08:45:36 2002
@@ -242,6 +242,7 @@
#define __NR_removexattr 235
#define __NR_lremovexattr 236
#define __NR_fremovexattr 237
+#define __NR_lutime 238
/* user-visible error numbers are in the range -1 - -124: see <asm-i386/errno.h> */
-
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This archive was generated by hypermail 2b29 : Sun Jun 30 2002 - 22:00:10 EST